Chris Smalling suffered a groin injury during Manchester United's loss to Wolfsburg in the Champions LeagueGetty

Manchester United suffered a double injury blow in what was a disappointing night for the Red Devils as they were knocked out of the Champions League by Wolfsburg. Matteo Darmian was the first of the casualties when he limped off with a hamstring strain just before the first-half, Chris Smalling suffered a suspected groin strain in the latter stages of the game, but continued to play as Louis van Gaal had already made all his three changes.

The Old Trafford club travelled to Germany with a squad already depleted by injuries with the manager forced to hand a full debut to 18-year-old Uruguayan Guillermo Varela at right-back due to lack of options in defence. Darmian started at left-back and was replaced by yet another teenager after Cameron Borthwick-Jackson came on late in the first-half. Smalling, meanwhile, was struggling at the end of the game, and the manager had to shift him into attack due his inability to help in defence.

"Matteo Darmian has a hamstring injury and Smalling probably a groin injury," Van Gaal said, as quoted on United's official site. "Smalling could not jump at the moment of the set plays and that goal [Wolfsburg's third] was also because of that. He had to give it [defensive responsibility] to another player and that's always a question of communication and quality. With Naldo [who scored twice], we knew in advance that he was a very important header for them."

United are already short on defensive cover, and the duo join Luke Shaw, Antonio Valencia, Phil Jones and Marcos Rojo on the sidelines, and the Red Devils are facing the prospect of travelling to Bournemouth on Saturday (12 December) without six first-team defenders.

"I don't know, it's happened this evening, but normally they are out for Saturday," the former Bayern Munich and Barcelona manager added.